////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
// WjCryptLib_Aes
//
// Implementation of AES block cipher. This implementation was modified from LibTomCrypt written by Tom St Denis
// (https://github.com/libtom). Modified by WaterJuice retaining Public Domain license.
// Derived from Public Domain source by original authors:
// Vincent Rijmen
// Antoon Bosselaers
// Paulo Barreto
//
// AES is a block cipher that operates on 128 bit blocks. Encryption an Decryption routines use an AesContext which
// must be initialised with the key. An AesContext can be initialised with a 128, 192, or 256 bit key. Use the
// AesInitialise[n] functions to initialise the context with the key. Once an AES context is initialised its contents
// are not changed by the encrypting and decrypting functions. A context only needs to be initialised once for any
// given key and the context may be used by the encrypt/decrypt functions in simultaneous threads.
// All operations are performed BYTE wise and this implementation works in both little and endian processors.
// There are no alignment requirements with the keys and data blocks.
//
// This is free and unencumbered software released into the public domain - December 2017 waterjuice.org
////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
#pragma once
////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
// IMPORTS
////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
#include
////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
// TYPES
////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
#define AES_KEY_SIZE_128 16
#define AES_KEY_SIZE_192 24
#define AES_KEY_SIZE_256 32
#define AES_BLOCK_SIZE 16
// AesContext - This must be initialised using AesInitialise128, AesInitialise192 or AesInitialise256
// Do not modify the contents of this structure directly.
typedef struct
{
uint32_t eK[60];
uint32_t dK[60];
uint_fast32_t Nr;
} AesContext;
////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
// PUBLIC FUNCTIONS
////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
// AesInitialise
//
// Initialises an AesContext with an AES Key. KeySize must be 16, 24, or 32 (for 128, 192, or 256 bit key size)
// Returns 0 if successful, or -1 if invalid KeySize provided
////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
int
AesInitialise
(
AesContext* Context, // [out]
void const* Key, // [in]
uint32_t KeySize // [in]
);
////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
// AesEncrypt
//
// Performs an AES encryption of one block (128 bits) with the AesContext initialised with one of the functions
// AesInitialise[n]. Input and Output can point to same memory location, however it is more efficient to use
// AesEncryptInPlace in this situation.
////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
void
AesEncrypt
(
AesContext const* Context, // [in]
uint8_t const Input [AES_BLOCK_SIZE], // [in]
uint8_t Output [AES_BLOCK_SIZE] // [out]
);
////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
// AesDecrypt
//
// Performs an AES decryption of one block (128 bits) with the AesContext initialised with one of the functions
// AesInitialise[n]. Input and Output can point to same memory location, however it is more efficient to use
// AesDecryptInPlace in this situation.
////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
void
AesDecrypt
(
AesContext const* Context, // [in]
uint8_t const Input [AES_BLOCK_SIZE], // [in]
uint8_t Output [AES_BLOCK_SIZE] // [out]
);
////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
// AesEncryptInPlace
//
// Performs an AES encryption of one block (128 bits) with the AesContext initialised with one of the functions
// AesInitialise[n]. The encryption is performed in place.
////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
void
AesEncryptInPlace
(
AesContext const* Context, // [in]
uint8_t Block [AES_BLOCK_SIZE] // [in out]
);
////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
// AesDecryptInPlace
//
// Performs an AES decryption of one block (128 bits) with the AesContext initialised with one of the functions
// AesInitialise[n]. The decryption is performed in place.
////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
void
AesDecryptInPlace
(
AesContext const* Context, // [in]
uint8_t Block [AES_BLOCK_SIZE] // [in out]
);